1. Field of the Invention
The present invention generally relates to locks and, more particularly, to an improved lock and protective cover assembly.
2. Prior Art
A number of covers have been devised to protect locks against the elements. For the most part, such covers have been made of non-corrodable metal, such as aluminum or magnesium, or of relatively stiff and inflexible plastic to seal off the locks from moisture, dirt, rusting and the like. Such covers are normally comprised of two or more hinged or snapped together pieces. See, for example, U.S. Pat. No. 4,317,344 wherein there are disclosed a pair of top and bottom boots which clamp together over the lock body. In U.S. Pat. No. 3,848,440, a similar construction is disclosed with a lid snap fitted to a bottom casing. U.S. Pat. No. 3,858,419 discloses a similar arrangement, as do U.S. Pat. Nos. 4,224,813 and 3,983,725. U.S. Pat. Nos. 4,134,280, 4,286,445 and 4,218,902 are also similar.
In each instance, two or more portions of the protective casing must be pulled apart or a hinged trap door therein must be opened in order to permit access to the lock keyhole for operation of the lock. Such devices tend to become very brittle and stiff in use, so that their components become difficult to separate and reassemble and have a tendency to wear rapidly. This is particularly true when the ambient temperature is very low, as in the winter in northern climates. Moreover, such devices require complicated fabricating techniques and are relatively expensive.
Accordingly, it would be desirable to provide an improved lock and cover assembly wherein the cover is easy to install and to remove and is inexpensive, durable and efficient in all kinds of weather to fully protect the lock. Such cover should be capable of being made in a single molding operation or simple forming operation and be unitary in structure.
An assembly which overcomes most of the foregoing defects is set forth in U.S. Pat. No. 4,651,543. In that patent, a one-piece stretchable cover is disclosed which is stretched over a lock and which provides an openable bottom slit. The cover is intended to be left in place and is somewhat difficult to install over a lock, unless it is made very loose and/or highly elastic. Its elasticity may be so reduced with age and weathering that it cannot be removed from the lock for oiling and repair of the lock, etc., without ripping and destroying the cover.
Accordingly, there remains a need for a simplified easily installable and removable lock cover which will allow periodic inspection and oiling of a lock while retaining the integrity and weather-sealing capability of the cover. Such cover should be flexible and resilient but should not require extreme stretchability in order to be easily installed on and removed from the lock.